Your water pressure

No matter what the pressure is in the mains network, your old water supply pipe may be restricting the flow of water to your property. The maximum amount of water your supply pipe can carry will be effected by its internal diameter. This will appear to you as poor pressure, leaks from old water supply pipes or fittings will also reduce the water pressure.

The pressure of the water coming through your taps can sometimes vary and there are a number of reasons for this. Water companies aim to ensure that your water pressure is no less than a target of 1 bar at the boundary of your property. Water companies have devices monitoring pressure levels throughout there mains. Water pressure in the mains network is not always constant throughout the year, nor from hour to hour throughout the day. It changes in response to the demand for water being placed on the distribution system.

There may be some occasions when a water company cannot meet it's targets. This may be owing to high water demand during hot sunny spells when temporary loss of water pressure is unavoidable. In addition, routine maintenance and improvements to the mains network or burst mains can temporarily reduce pressure - this should disappear within a day or so unless they advise you otherwise.

Pressure - The water supply to your house comes from a high pressure mains network maintained by the local water company. But the condition of the supply pipe and the arrangement of the water pipes in your home can substantially reduce that pressure by the time it gets to your taps

Flow - The flow of water to your taps can also be restricted by the condition of your water pipes. Along with the pressure from the mains network the maximum amount of water your pipes can carry will be affected by:

The diameter (size) of your pipes.

Any leaks you may have on your supply.

Corrosion in the pipes.

The demand for water in your property at any one time.

The condition of your appliances.

The water flow and pressure in your home will be affected by the length of the supply pipe. On longer supply pipes, particularly those with a smaller internal diameter, the water company may be meeting the target water pressure at the boundary, but the pipe on premises may be too small to deliver the flow of water to your property, resulting in what appears to be low pressure.

Some pressure problems can be caused by faulty, damaged and leaking pipes and fittings, for example ball valves and stop taps inside your home.
If the pipes in your home are old, they may have become corroded, restricting the water flow. CONTACT EPS to check this for you.

Leaks from pipes or fittings will reduce water pressure. If you have a water meter, check for a leak by taking a meter reading just before going to bed and again in the morning. If the figures are different, you may have a leak. If you do not have a meter, listen for hissing sounds from inside pipes or look for damp patches.

A partially closed branch stop tap inside your home could be the cause of low water pressure. Gently opening up the tap may increase the pressure. To fully open the tap, you should open and close it several times until the number of turns from open to closed is constant. Do not leave the tap fully open. Turn it back a quarter of a turn to stop it seizing up.

Systems using Combination Boilers

After flowing through your underground supply pipe, the water goes to your combination boiler. The boiler then supplies all the hot taps inside your home. Combination boilers will not work below certain water pressure levels. While conventional boilers can run on as little as 0.5 Bar, combination boilers generally need more for them to function effectively. The pressure your boiler needs sometimes may be above what the local water authority aims to supply in their water mains (1 Bar measured at the boundary of your property). If your system's pressure has been assessed to be below 1 Bar, it is likely that this is due to the condition of your pipe work. It can be the case that some combination boilers are only capable of supplying one hot tap with water at any one time. Or, the pressure at your cold-water taps may reduce if they are run at the same time as a hot tap because the boiler is not powerful enough for the size of your system. If you are planning to install a new boiler, make sure that the installer checks that your chosen system will work effectively at a water pressure of 1 Bar. If there is a reduction in the pressure it will be due to plumbing issues in your water pipes, Though you must remember that water pressure is not constant and that demand, especially during the busy morning and evening periods, can reduce the overall water pressure in the water mains network, and affect your supply. If this becomes a problem, you may want to look at increasing the size of your water supply pipe or renewing the existing corroded pipe work.

Systems relying on tank height

Water goes to your kitchen tap after flowing through your underground supply pipe. Water then goes to a storage tank in your loft space, and this tank supplies all the other taps in your home as well as your hot-water system. The height of the tank above your supply pipe will affect how quickly it will refill (pressure is lost the higher water has to be lifted). The height of your tank above your other taps will affect the pressure at which water is fed to those taps.

Shared Supply Pipes (Common Supply)

For some properties, the problem is caused by sharing a supply pipe from the water main. This can be a problem if the supply is too small, in poor condition (for example, leaking or old), or if properties sharing a supply use water at the same time. It can also be particularly noticeable at busy times when many properties sharing a supply pipe are placing demands on the water supply. So, a supply that seems fine at some times of the day may not be at other times. If you and your neighbour share a supply pipe, you are jointly responsible for it from your property to the boundary stop tap. The houses in the example below have a shared supply pipe and a joint responsibility for maintaining and repairing it. If you have reduced water pressure and you are on a shared supply pipe, talk to your neighbours to see if they are experiencing the same problem. If so, you may want to look at installing a separate independent service pipe from your property to the water main or, at a joint cost, renewing / increasing the size of the shared supply pipe.

NOTE: The Local Water Authority may make an additional charge for the connection to the water main.

Supply pipe size

Flow and pressure in your home will be affected by the length of the supply pipe. On the longer supply pipes, particularly those with a smaller internal diameter, the pipe may be too small to deliver the flow of water to your property that you want even though the pressure is good at the boundary.

Stop Taps

A partly closed stop tap inside your home could be the cause of some water-pressure problems. Gently opening up the tap may increase the pressure. To fully open the tap, you should open and close it several times until the number of turns from open to closed is constant. Do not leave the tap fully open. Turn it back a quarter of a turn to stop it seizing up.

Leaks

Leaks from pipes or fittings will reduce the water pressure. If you think you have a leak you can check by:

If you have a water meter, you can check for a leak by taking a reading from your meter just before going to bed and again in the morning before you have used any water. If the figures are different, you may have a leak.

If you do not have a meter, listen for hissing sounds from inside pipes or look for damp patches or very obvious green patches on your grass.

Location

Pressure will be affected by the height of a property in relation to the local area around it. If you property is at the top of a hill, you may receive lower pressure than properties that are at the bottom of the hill, especially during busy times of the day such as morning or early evening and during the summer. The local Water Authority will aim to supply a water pressure of 1 Bar at the boundary to your property, however you might want to consider installing a water accumulator. This is a relatively new device that holds water in a vessel during those periods when demand to your property is low and releases that water as you need it at busy times.

Heating appliances and showers

The plumbing layout in your property may affect the pressure at which water is supplied to your taps. It may also affect your shower. Many new showers will need a minimum level of flow and pressure to work effectively. Some will need to be supplied directly from the mains (not from a tank in the loft). In older showers, limescale may build up and cause poor flow at the shower head. Always clean your shower head every three months to prevent limescale building up. If you cannot remove the limescale, try replacing the shower head and hose attached to it with new ones.

If you are planning to fit a new shower or heating system, make sure you check that your planned system can work efficiently at the pressure of 1 Bar. Any reduction to this pressure is likely to be due to plumbing problems with your water pipes.